High AlTedTude Flight

I decided to send my tiny teddy bear on a world trip (via post to other people) and get photos of him in as many different & interesting places (maybe doing daft things) as possible. All photos e mailed back will be posTed on his personal web site. It’s a stupid idea… but hey, someones gotta’ have ’em.

Steve created a web site where he posts a photograph from each new place that Ted visited on his amazing travels. By the time of my flight, Ted had travelled over 400,000 miles, though the original Ted had gone AWOL and was replaced by “Mrs Ted” who travels the world looking for her lost soul mate.

Coincidentally, it was that same forum that got me started HABbing in February 2011 when someone else posted a link to a video where 2 guys flew a very simple payload under a weather balloon. The video was nicely put together and I very quickly decided to do a weather balloon flight myself. So it was only fitting that I closed the circle by offering to send Ted up into “space” under a weather balloon. I did just that in August 2012, after I’d completed several flights and felt confident that Mrs Ted’s series of adventures wouldn’t be terminaTed by me losing or dumping her in the North Sea! Even so I made the offer with trepidation. After a brief discussion about risks, Steve accepted my offer and put me down in the October slot of Mrs Ted’s very full diary.

October arrived and so did Mrs ted. I immediately put her on a training course run by my experienced Space Ranger:

Meanwhile however the winds just wouldn’t allow for a safe flight. I was hoping for a launch before my holidays (RV tour of California) but that wasn’t possible. When I got back the winds again prevented the flight. Fortunately the next “owner” didn’t need Mrs Ted for a few more days, and the wind predictions were good for a few short hours on one day – Sunday 4th November. From the predictions I could see that a launch in the morning would land perilously close to the coast, but the mid-late afternoon was OK. Of course in November the sun sets quite early so I actually had a launch slot of only a couple of hours or so! No pressure then!

Talking of pressure, there was a danger that if the balloon exceeded specification and burst higher than predicted, the strong eastward wind at altitude would move the landing point up to, or beyond, the coast. So to prevent that I decided to put a lot more gas into the balloon than otherwise needed. More on that later!

I also decided to use 2 separate trackers, to reduce the chances of a problem causing us to not know where Mrs Ted was. The primary tracker was a Raspberry Pi, transmitting telemetry and also “live” images taken by a webcam. I put a Canon camera into the same box, with Mrs Ted out on a balsa wood stick. She was tied to that with many loops of matching grey cotton thread, and she had a separate safety line of very strong carbon fibre thread linking her directly back to the payload. This is essential as balsa can break even during descent when the ‘chute lines can snag on the stick. I carefully positioned both cameras to get a good view, like this:

Another HABber Ali kindly came along to help with the launch. He got a bit stuck in traffic, and I was behind anyway with the payload build having managed to remove a chunk of finger with a (very) sharp knife! Once that was patched up, and Ali had arrived, we tied and taped up the payload:

The secondary tracker Buzz is in the pink egg at the front of my new launch table. I cut 2 holes into the top to allow for payload aerials to poke through. Here’s a view of Mrs Ted with the pink Buzz payload behind her, and a roll of duct tape (this hobby uses a lot of tape!) next to her:

Julie then joined us and we drove up the road to my launch site. Here I am checking the telemetry before we continued.

The fill was normal though my newly damaged finger didn’t help when tying off the balloon! I decided to let Ali do the knots, and fortunately he turned out to be something of an expert! As mentioned earlier I decided to over-fill the balloon. The calculated neck lift was a fairly hefty 3kg, but I opted to increase that to 3.5kg to make really sure the balloon burst before it was too late. The very inflated balloon behaved in the air like a massive jelly, with the envelope wobbling rapidly if the line was pulled quickly. Here’s Ali holding on to the balloon just before the launch.

The launch itself was straightforward, with little wind. I asked Ali to launch, and he was a bit surprised by just how quickly the balloon yanked the line out of his hand. With nearly 3kg of net lift that thing took off very quickly!

We quickly packed up and took the cylinder and other stuff home. Ali had to leave so Julie and I jumped back into the chase car to head for the expected landing site near Braintree in Essex. As we headed for the M4 Julie checked online and found that we had no live images coming in. Apparently nobody could receive the signal, so we tried in the car and couldn’t receive it there either! This was a surprise as well as a disappointment, since we had a nice strong signal on the ground at the launch site. For now we didn’t know what had gone wrong. Fortunately however the Buzz backup payload was transmitting and being received just fine, so we tuned to that.

The road to the M4 was flooded, but no problem in our 4×4! We took the M4 east to the M25, then that round to the M11 which (if the burst happened when planned) would be the best road to take. Meanwhile Mrs Ted was ascending rapidly as planned, averaging out at 7 metres per second (most flights ascend at around 5m/s). The expected burst altitude was 27km though anything below 32km would be OK. We were on the M25 when we saw that the balloon had burst at 29,527 metres, and I was pleased and relieved to see that! Here’s a graph showing the ascent and descent:

The expected landing spot was indeed near to Braintree, so we took the M11 north. Mrs Ted landed before we got to the A120 which we took east towards the landing site. The other enthusiasts on IRC (Internet Relay Chat) gave us a postcode to type into the car sat nav, and then confirmed the route for us. Here’s the live map showing the route of both the flight and the chase car:

As we got closer I kept an eye on the touchscreen panel mounted on the dash of my 4×4. This gave me a distance and direction from car to payload. As we got very close we could see that the payload was on our left and then behind us as we passed the field that it was in. I turned as soon as I could, then parked up on the pavement opposite the landing spot. The screen showed the payload was only 73 metres away, so I grabbed a torch and aimed across the field. Fortunately I’d put some Hi Viz reflective tape on the main payload, and this lit up brightly under the torch light. After quick trek across the field I returned with the payloads and chute in my hands and a sizeable amount of Essex mud on my shoes! Here’s the map zoomed in to show the path of the payloads being carried across the field:

Mrs Ted was, to my considerable relief, still attached to the box. The balsa wood support had broken on landing, but the carbon fibre safety line was intact with Mrs Ted dangling on the end of it. The camera lens was still out so I pulled the camera from the payload to view the shots. To my disbelief the camera didn’t respond to any button presses – even the power button – it had just locked up! I removed and re-inserted the batteries and it happily powered up, so I checked the photos and ….. none at all from the flight! The last photo was taken when the payload was on the table at the launch site. So for some (still unknown) reason the camera had failed, despite having plenty of capacity in the batteries and plenty of space on the SD card. If the problem had been “finger trouble” then the camera would have withdrawn the lens soon after recording had stopped, so the whole thing is a mystery.

So, at this point I thought the flight had been wasted. Yes, Mrs Ted was safe, but the live images were never received and the main camera had failed. So no flight pictures at all. I examined the payload and found that the plug on aerial cable wasn’t fully tightened, so that could explain the lack of live images, but knowing the problem didn’t get those pictures back. I cleared the mud from my shoes and got back in the car to drive home.

Fellow enthusiast Dave “number10” called through. He had tried to get to the landing site as he lived quite close, but got stuck on a flooded road with an AA van blocking traffic from attempting to drive through. In the rush to get Mrs Ted back and the worry about those lost images, I’d forgotten that he was on his way! With Mrs ted recovered we all just went home.

It was about an hour later when I remembered a key fact. On my first Pi flight my code just deleted all images after transmission, but for this flight I changed it to copy those images (transmitted or rejected) to a “keep” folder on the SD card. So, provided the Pi had stayed running throughout the fly, then we should have a complete set of images! Needless to say I started driving a little bit quicker from that point onwards!

When we got home I quickly posted on pistonheads to say that Mrs Ted had been recovered and was safe. I kept quiet about the yet unknown situation about those images. I then put the SD card into a spare Pi and connected that up to my main PC via my home network, and then copied all the image files over and started to view them. To my considerable relief there were plenty of very good photos to see! With the late launch the light stopped probably before the burst, but some of the sunset images during the ascent were great. Here are some of my favourites:

So, in the end, a successful flight though I need to check the aerial cable next time, and that camera I used will be binned. Mrs Ted was recovered and we have photographic evidence of her flight!